using the internet7
TRANSCRIPT
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Technology In Action
Chapter 3Using the Internet:
Making the Most of the Web’s Resources
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Communications
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Communications
•Communication is the transmission of a signal from a sender to a receiver by way of a medium.
•The signal contains a message composed of data and information.
•For communication to be effective, both sender and receiver must understand the signals and agree on the way they are to be interpreted.
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An Overview of Telecommunications
Telecommunications: the electronic transmission of signals for communications
Telecommunications medium: anything that carries an electronic signal and interfaces between a sending device and a receiving device
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Telecommunications
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Telecommunications
It starts with a sending unit (1), such as a person, a computer system, a terminal, or another device, that originates the message.
The sending unit transmits a signal (2) to a telecommunications device (3).
The telecommunications device performs a number of functions, which can include converting the signal into a different form or from one type to another. The telecommunications device then sends the signal through a medium(4).
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Telecommunications
A telecommunications medium is anything that carries an electronic signal and interfaces between a sending device and a receiving device.
The signal is received by another telecommunications device (5) that is connected to the receiving computer (6).
The process can then be reversed and another message can go back from the receiving unit (6) to the original sending unit (1).
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Telecommunications
Data Communication – A specialized subset of telecommunications that refers to the electronic collection, processing, and distribution of data – typically between computer system hardware devices.
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Functions of a modem
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Channel Bandwidth
Telecommunications professionals consider the capacity of the communications path or channel when they recommend transmission media for a business
Channel bandwidth: the rate at which data is exchanged over a communication channel Usually measured in bits per second (bps)
Narrowband channels provide rates up to 64K BPS (twisted pair)
Broadband begins with 1.5 MBS
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Basic Communications Channel Characteristics
Simplex channel A communication channel that can transmit data in
only one direction
Half-duplex channel A communication channel that can transmit data in
either direction, but not simultaneously.
Full-duplex channel A communication channel that permits data
transmission in both directions at the same time.
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Simplex, half-duplex and full duplex transmission
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Parallel Transmission
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Serial Transmission
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The Internet: The Basics
Origin of the InternetThe Internet vs. the WebClients and serversConnecting to the Internet
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Client and Server
Client computer: Users connect to the Internet Request data and Web pages
Server computers: Store Web pages and data Return the requested data to the client
Server
Client
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Client/Server Systems (continued)
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Client-Based Architectures
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Two Tier Client-Server Architecture
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Three Tier Client-Server Architecture
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Components of a simple network
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Client/server computing on the Internet N-tier Architecture
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Packed-switched networks & packet communication
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TCP/IP and OSI Model
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Message transmission using layers
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Connecting to the Internet
Dial-up connection: Uses standard telephone
line Least costly connection Requires a modem
Converts analog and digital signals
Slowest connection speed (56Kbps)
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Broadband Connections
Digital Subscriber Lines Faster than dial-up
Upload (300Kbps – 1.5Mbps) Download (1Mbps – 1.5Mbps)
Requires special DSL modem
DSL modem
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Broadband Connections
Cable: Uses TV coaxial cable Fast connection speed
(500Kbps – 4Mbps) Speed depends on
number of users Not available in all areas Requires a cable modem
Coaxial cable
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Microwave Transmission
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Satellite Connections
Uses a satellite dish and coaxial cable Download speed 500
kbps Upload speed 100
kbps Signal is affected by
location and weather
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Satellite Transmission
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Network Types: Local Area Network
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Network Types: Wide Area Network
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Types of Networks
Type Area
Local Area Network (LAN) Up to 500 meters (half a mile); an office or floor of a building
Campus Area Network (CAN) Up to 1,000 meters (a mile); a college campus or corporate facility
Metropolitan Area Network (MAN)
A city or metropolitan area
Wide Area Network (WAN) Transcontinental or global area
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Network Topology
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Network Topology
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Network Topology
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Ring Based Design
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Star Based Design
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Full and Partial Mesh Design
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Virtual Private Network
Internet
VPN Tunnel
VPN Tunnel
VPNDevice
Backbone
Backbone
Office
Office
VPNDevice
VPNDevice
TelephoneLine
ISP
Employee’sHome
AccessServer
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Communications Media
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Communications Media (continued)
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Twisted-Pair Wire Cable
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Coaxial Cable
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Fiber Optic
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Types of Optical Fiber
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Communications Software and Protocols
Communications protocol: a set of rules that govern the exchange of information over a communications channel
Protocols govern several levels of a telecommunications network, such as: Hardware device level Application program level
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How the Internet Works
Routing Messages over the Internet
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How the Internet Works (continued)
Several Ways to Access the Internet
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Comparing Internet Connection Options
Connection Option
Maximum Upload Data Transfer Rate (approximate)
Maximum Download Data Transfer Rate (approximate)
Dial-Up 56 Kbps 56 Kbps
DSL (ADSL)
300 Kbps 1 Mbps
DSL (SDSL)
1.5 Mbps 1.5 Mbps
Cable 500 Kbps 4 Mbps
Satellite 100 Kbps 500 Kbps
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Choosing an ISP
Factors to consider: Customer service Local access numbers E-mail options Cost Trial period
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Internet Service Providers
ISP: Internet service provider Provide user access to
the Internet National, regional, or
local companies
OSP: Online service provider Provide online
proprietary content as well as Internet access
AOL, CompuServe, MSN
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The Origin of the Internet
ARPANET: Advanced Research Projects Agency Network Funded by the U.S. government in the 1960s Allowed computers at leading universities and research
organizations to communicate with each other over great distances
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IT INFRASTRUCTURE
• Electronic accounting machine era: (1930–1950)
• General-purpose mainframe and minicomputer era: (1959 to present)
• Personal computer era: (1981 to present)
• Client/server era: (1983 to present)
• Enterprise internet computing era: (1992 to present)
Evolution of IT Infrastructure: 1950–2005
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Evolution of IT Infrastructure: 1950–2005
Figure 6-3
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The Web
The Web is a part of the Internet distinguished by: common communication protocols TCP/IP and HTML special links (called hyperlinks)
Web invented in 1989 by Tim Berners-Lee1993, National Center for Supercomputing
Applications releases the Mosaic browser Developers of Mosaic release Netscape (1994)Netscape is beginning of Web’s major growth
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The Internet vs. The Web
Internet – part of the system that is primarily hardware infrastructure (telecommunications, routers, servers, disk drives, etcetera)
Web – part of the system that contains intellectual property in many multimedia formats (test files, graphic files, sound files, video files, etc.)
INTERNET
WWW
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Web Sites
Web site: Collection of related Web pages First page known as Home or Index page
Web page: HTML document
Text and graphics Unique address Hyperlinks
Home page
Related pages
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The World Wide Web (continued)
Hypertext Markup Language (HTML): the standard page description language for Web pages
HTML tags: codes that let the Web browser know how to format text - as a heading, as a list, or as body text - and whether images, sound, and other elements should be inserted
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URL
URL: Uniform Resource Locator Unique Web page address
URL http://
Protocol identifies the means of access
www.nytimes.com/
Domain name contains the host and top-level domain
Pages/cartoons/
Path identifies the subdirectories
within the Web site
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Hyperlinks
Provide access to other Web pages
Specially coded text or graphics
Cursor becomes a hand with finger pointing upward
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Internet Communications
Instant MessagingVoice over Internet
(VoIP)WeblogsPodcastsWebcasts and WikisChat RoomsNewsgroupsE-mail
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Instant Messaging
Real-time text-based conversations
Set up a list of contacts Buddy list
Contacts must be onlineIM software detects
presence Example: AOL Instant
Messenger
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Voice over Internet Protocol
VoIP - The Internet as a means to place phone calls
Uses technology similar to e-mail to send voice data digitally
Requires a microphone an Internet connection A VoIP provider
Services differ Free services require an account on both ends Paid services connect phone to computer Cable and DSL providers offer phone through broadband WiFi IP phones call through Internet hotspots and
wireless networks
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How IP Telephony Works
Figure 8-13
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Cisco Family of IP Phones
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Weblogs (blogs)
Known as blogsAvailable to the
publicSimple to create,
read, and manageEntries listed on a
single pageMost recent entry
at the top
• SearchableSearchable• Some are personalSome are personal• Many are focused on a Many are focused on a
topictopic
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Podcasts
Video blog (vlog) – entries are video clipsPodcasts – compressed audio/video files
distributed on the InternetRSS (Really Simple Syndication) technology
allows constant updates for subscribersPodcasts are all over the Web
Requires “aggregator” software to gather podcasts
Requires media player software to play themSimple to create and attach RSS files
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Webcasts and Wikis
Webcasts broadcast audio/visual files but are not updated use streaming media
A wiki is a Web site that allows anyone to change its content
Wikis provide an excellent source for collaborative writing
Unlike blogs, wikis can be edited for a “common” opinion
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Electronic mail
Primary means of communication
E-mail accounts Client-based Web-based
Spam Prevention
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Chat Rooms
Real-time text-based conversationsRooms focus on specific topics or interestsIdentity protection
Username
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Newsgroups
Online discussion forumsPost and reply to messages
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Social Networking
Social networking sites like MySpace.comMembers share common interestsMembers communicate by voice, chat, instant
message, video, and blogs Members create personalized profiles Growth has been explosive Risks must be recognized and reduced
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Web Entertainment
Multimedia: Involves forms of media
and text Graphics Audio Video
Streaming audio and video Plug-in
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Online Annoyances
Spam – electronic junk mailPop-ups – intrusive advertisingCookies – tracking user’s browsing habitsSpyware – programs that collect data from a
user’s computerMalware - software that has a malicious
intent Phishing and Hoaxes – Ruses to fool and
maybe steal from users
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Spam
Junk e-MailSpam filtersAntispam
practices
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Pop-ups
Usually advertisingPop-up
automaticallyPop-up blockers
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Cookies
Text files stored on client computers when visiting Web sites
Used on return visits to Web sites
Unique ID numberPersonal information
rememberedPrivacy risk
Selling information
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Spyware
Added as a program piggybacked with a requested program
Gathers information, usually about surfing habits
Antivirus software doesn’t detect it
Spyware removal programs are required
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Malware
Software that has a malicious intent Spyware is a form of malwareOther forms are viruses, worms, and Trojan
horsesDesigned to render a computer useless or
penetrate it completely
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Phishing and Hoaxes
Phishing is a phony communicationAttempts to scam someone into sending
vital informationHoaxes are attempts to scam people into
sending money, or join a chain letter
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Navigating the Web: Web Browsers
Computer softwareGraphicalEnables Web
navigationPopular browsers:
Internet Explorer Netscape Navigator Camino (Mac OSX)
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Browser Toolbars84
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Getting Around the Web
Web sitesURLsHyperlinksFavorites and
Bookmarks
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Current Top-Level Domains
..aeroaero Members of the air transport Members of the air transport industryindustry
.biz.biz BusinessesBusinesses
.com.com Can be used by anyoneCan be used by anyone
.coop.coop Cooperative associationsCooperative associations
.edu.edu Degree granting institutionsDegree granting institutions
.gov.gov United States governmentUnited States government
.info.info Information service providersInformation service providers
.mil.mil United States militaryUnited States military
..museum museum MuseumsMuseums
..name name IndividualsIndividuals
.net.net Networking organizationsNetworking organizations
.org.org Organizations (often nonprofits)Organizations (often nonprofits)
.pro .pro Credentialed professionalsCredentialed professionals
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Favorites and Bookmarks
List created of favorite Web pages
Easy method of returning to Web pages
Internet Explorer uses Favorites
Netscape uses Bookmarks
Live Bookmarks use RSS
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Tabbed Browsing
Found on Firefox and Safari browsers Available on the latest version of Internet
Explorer Multiple pages in same browser window
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Search Engines
User keys word or phrase in search box
“Spider” or “Web Crawler” program scans Web pages
Results are indexed and sent to the client
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What do YOU use the web for?
???
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• Information technology infrastructure: The Internet provides a universal and easy-to-use set of technologies and technology standards that can be adopted by all organizations.
• Direct communication between trading partners: Disintermediation removes intermediate layers and streamlines processes.
ELECTRONIC BUSINESS, ELECTRONIC COMMERCE, AND THE EMERGING DIGITAL FIRM
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Open System Interconnect Model
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ELECTRONIC BUSINESS, ELECTRONIC COMMERCE, AND THE EMERGING DIGITAL FIRM
• Round the clock service: Web sites available to consumers 24 hours
• Extended distribution channels: Outlets created for attracting customers who otherwise would not patronize a firm
• Reduced transaction costs: Costs of searching for buyers declines
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How the Internet Reduces Transaction Costs
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• Information asymmetry: One party in a transaction has more information than the other. The Internet decreases information asymmetry.
• Increases richness: The Internet increases the depth, detail, and scope of information.
• Increases reach: The Internet increases the number of people who can be contacted efficiently.
ELECTRONIC BUSINESS, ELECTRONIC COMMERCE, AND THE EMERGING DIGITAL FIRM
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The Changing Economics of Information
Figure 4-1
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Conducting Business Over the Internet
E-Commerce: Electronic commerce Business-to-consumer (B2C) Business-to-business (B2B) Consumer-to-consumer (C2C) Secure transactions
Manufacturer
Suppliers
Retailer
B2BE-commerce
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Business-To-Consumer Advantages of E-commerce:
• Customer-centered retailing: Closer and more personalized relationship with customers is possible
• Web sites: Provide a corporate-centered portal for the consumer to quickly find information on products, services, prices, orders
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• Disintermediation: The elimination of organizations or business process layers responsible for certain intermediary steps in a value chain, reducing costs to the consumer
• Reintermediation: The shifting of the intermediary role in a value chain to a new source, adding additional value to the consumer
Business-To-Consumer
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The Benefits of Disintermediation to the Consumer
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Clickstream tracking tools:
• Collect data on customer activities at Web sites and store them in a log
Interactive Marketing and Personalization
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Web Site Visitor Tracking
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• Create unique personalized Web pages for each customer
• Increased closeness to customer increases value to the customer, while reducing costs of interacting with the customer
Web Personalization
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Web Site Personalization
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• Compares information gathered about a specific
user’s behavior at a Web site to data about other
customers with similar interests to predict what
the user would like to see next. The software then
makes recommendations to users based on their
assumed interests.
Collaborative filtering:
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• The use of Web sites to provide customers with access to information and answers to questions
• Replacing human call center operators and clerks
• UPS.com: Customer tracking of packages
• Orbitz.com: Customer self-help for organizing and managing a trip
• Dell.com: “My Order Status” facility
Customer self-service:
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• Electronic Data Interchange (EDI): Enables the computer-to-computer exchange between two organizations of standard transactions. Currently 80% of B2B e-commerce uses this system.
• EDI is being replaced by more powerful Web-based alternatives.
Business-to-Business Electronic Commerce
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Figure 4-5
Electronic Data Interchange (EDI)
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The largest Web-based form of B2B commerce
Private B2B extranets that focus on continuous business process coordination between a small group of companies for collaboration and supply chain management.
Wal-Mart uses its own private network to coordinate more than 15,000 suppliers to its stores.
A Private Industrial Network
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A Private Industrial Network
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• Distributors: B2B online catalogs provide buyers with access to thousands of parts and other goods (Grainger.com)
• Procurement platforms: Platforms for purchasing goods and materials and also sourcing, negotiating with suppliers, paying for goods, and making delivery arrangements (Ariba.com)
Four different types of Net Marketplaces:
Net Marketplaces
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• Independent exchanges: Third-party Net marketplace
that is primarily transaction-oriented and that connects
many buyers and suppliers for spot purchasing
(Freemarkets.com, GEPolymerland.com)
• Industry consortia: Industry-owned Net marketplaces
used primarily for long-term sourcing of direct inputs
to production (ChemConnect.com)
Net Marketplaces
Four different types of Net Marketplaces: (Continued)
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A Net Marketplace
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Consumer-To-Consumer
I want that Dino!
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Electronic Commerce Payment Systems
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Electronic Commerce
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Now that I know hardware, software and network, I want to build something!
• Personal Video Recorder – record TV shows and watch
it at anytime, skip commercials• Slingbox http://www.slingmedia.com/• Build your own PVR
• A used computer, a wireless network card, TV
tuner/capture card, home wireless network,
ubuntu operating system, MythTV video
recording software (
http://www.byopvr.com/Sections+index-req-viewarticle-artid-10-page-1.html)
• How does it look?
http://www.youtube.com/watch?v=-jH_E3NmX8U
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